The invention relates to a microelectromechanical semiconductor component with cavity structure, wherein the semiconductor component has an active semiconductor chip with a microelectromechanical structure and a wiring structure on its top side, and wherein the microelectromechanical structure is surrounded by walls of at least one cavity, and a covering of the cavity is arranged on the walls.
A semiconductor component of this type is known from the document DE 103 10 617 A1. With this known semiconductor component, the components of the semiconductor component including an active semiconductor chip, a cover semiconductor chip and a wall structure between the active semiconductor chip and the cover semiconductor chip are embedded into a plastic housing composition, and thus take up a large space requirement.
What is more, the known semiconductor component the wiring structure on the top side of the active semiconductor chip that is connected via bonding connections to surface-mountable external contacts, bonding arcs of the bonding connections between the active semiconductor chip and the external contacts requiring a minimum height for the wall structure of the cavity which may not be undershot without jeopardizing the functionality of the semiconductor component. Consequently, the known semiconductor component cannot be minimized further in terms of its spatial extent.
The document DE 102 56 116 discloses an electronic device and a method for producing it in which the microelectromechanical structure is protected by a self-supporting, electrically conductive covering layer, the self-supporting covering layer being supported by passage lines, with the result that a cavity is formed over the active area region of the micromechanical structure.
With this electronic device, a prerequisite for cavity formation is the provision of a metal coating, in which case, furthermore, for the patterning of the cavity, the latter is firstly filled with a sacrificial structure made from suitable material, which subsequently has to be removed via openings.
The document DE 103 53 767 furthermore discloses a device for housing a micromechanical structure and a method for producing the same in which a photoresist that forms the cavity is provided as sacrificial material in uncrosslinked fashion in the region of the cavity. For this purpose, the uncrosslinked photoresist is surrounded by a crosslinked photoresist region with an opening via which the uncrosslinked sacrificial material can be removed by solvents.
With this device, openings for removing the sacrificial material are likewise necessary in order to ensure the cavity for the housing process. What is more, a costly method is required in order to realize such a device with cavity.